Electrical alarm-thermometer.



v R. HEDDLE.

ELECTRICAL ALARM THERMOMETER. APPLICATION FILED JUNE 21, 1909.

UNrrED STATES ROBERT HEDDLE, OF NELSON,

PATENT OFFICE.

BRITIH COLUMBIA, CANADA.

4 ELECTRICAL ALARMTTHERMOMETER. j

To all whmn 'itmay concern:

Be it known that I, ROBERT HEnpLE, a subject of the King of GreatBritain, resid ing at Nelson, British Columbia, Canada, have inventedcertain new and useful Improvements in Electrical Alarm-Thermoma ters;and I do declare the following to be a full, clear, and exactdescription of the invention, such as will enable others skilled in theart to which it appertains to make ahd use the same. p

1 My invention relates ters.

The object of the invention is to provide a unitary structure which maybe transported from place to place without breaking any connections ormaking any adjustments and which will act at certain predeterminedtemperatures to give an alarm.

- A still further object of the invention is the provision of meanswhereby a thermometer alarm may be adjusted to act at differenttemperatures of heat or-.cold. For instance, if it is desired to keep aroom within certain degrees of temperature, the device may be set sothat when'either one ofthe extremes of heat or cold is reached on thelimit set, an alarm will be given to notify the occupants of the room ofthe temperature condition of atmospherefitherein.

With these and other objects in View, the invention consists of certain.novel features of construction, combination and arrangement of parts aswill be more fully describedand particularly pointed "out in the apnpended claim.

In the drawings, Figure 1 is a front elevation of the device; Fig. 2 isa side eleva tion thereof witlfthe casing removed so as to clearly showthe inner portion of the thermometer, parts being shown in section; and-Fig. 3 is a horizontal sectional view taken" on "the line 3-3 of Fig. 1.m u ally to the drawing, 1 represents a suitable casing which? is.

Referring more especi adapted to be suspended upon'a' wallo'r othersuitable support by'an 'eye' piece 2 secured to the upper rear end ofthe casing-- The interior portion ofthe casing as defined by the back 3,front 4 and bottom 5,v is occu-' pied by the battery 6 which rests uponthe bottom and'by the magnet coils of the ringer R. The gen post of thisringer projects I through the ront plate 4 of the casing and.

has a gong plate G secured thereto.

to thermometers and particularly to electrical alarm thermomeitsbottonn'is a slotted screw bolt 7, adapted .to receive the thermostat 8,which in this instance is shown to be a pair of metallic bars rivetedtogether, which have difierent coefficients of expansion. Under normalconditions or with the thermostat subjected to medium temperatures, itremains in the vertical position parallel-with the side edges .of thefront plate 4.

Immediat elypbove the upper end of the thermostat, there is secured tothe front plate 4, a pivoting frame 9, which is provided with a pair ofcupped adjusting screws 10, adapted to receive an indicator pivot, 11,upon which the indicator 12, is carried. This indicator extendsdownwardly in frontof the thermostat 8, and has its pointed end 13,adapted to'travel over a graduated scale 14, which is perfectlyinsulated so as to pre-' vent electrical connection between the same andthe indicator 12; In the upper portion of the indicator, immediatelybelow its pivotal section, there is provided a slot 15, adapted to beengaged by a laterally extending pin 16, carried upon the upper end ofthe thermostat and immediately above the pivotal section of theindicator, is provided a'balanc e weight 17. I

. The lower end of the graduated scale 14, is secured to the front'plate4 by screws 18 and 19, the latter of which forms a terminal for theconductor 20, from one pole of the battery 6 and is adapted to engagethe exposed metallic portion of the scale and thereby forms electricalcommunication with their upper contacting portions. The screws 18 and19, are of course insulated from the scale 14, and current onlyflowstothe scale when the switch 21, which is in electrical contact with thescale is resting upon the terminal, screw 19, which is connected, asshown, by wayof conductor 20 to the battery, One terminal. of the ringeris.connected to the set screw 7,.by vway of wire 25 andthe oppositeringer terminal .is connected-to the battery by wire 26. When the switcharm 21, is in engagement Withthe contact screw'19, and the indicatorhand 12,

is m contactwith one of the slidable contacts 22 or23, the circuit frombattery is as foltact 22 or 23, indicator finger 12, thermostat -8,screw 7, to the ringer R, over the conductor'25, and back to batteryover wire 26'.

Passing through'the front plate adjacent Specification of LettersPatent. Patented Feb. 7, 1911'. App1ication filed June 21, 1909. SerialNo. 503,499.

lows: wire 20, screw 19, scale 14, eithercon- Thusthe ringer iscaused tooperate 'to indicate that the temperature either too cold ortoo warm.

From the foregoing description taken in of the room is connection withthe accompanying draw havin an indicator rovided with a pointed end wich is adapt to engage either of the sliding contacts when thethermostat is operated, said indicator having an elongated slot near theupper end ada tedto be engaged by the laterally extended pin, a batterycarried by said casing, a ringer also carelectrical connecried by thecasing having tion with said battery and contact, and "a switch in thecircuits carried by the scale.

In testimony whereof I have hereunto set. my hand in presence of twosubscribing witnesses.

' ROBERT HEDDLE.

\Vitnesse's: I v

A LOUISE A. ALmsoN, EDWARD A. GREASE.

